From owner-freebsd-current@FreeBSD.ORG Tue Oct 21 13:26:26 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id EE0A916A4B3; Tue, 21 Oct 2003 13:26:26 -0700 (PDT) Received: from cirb503493.alcatel.com.au (c211-30-75-229.belrs2.nsw.optusnet.com.au [211.30.75.229]) by mx1.FreeBSD.org (Postfix) with ESMTP id D02B643FDD; Tue, 21 Oct 2003 13:26:20 -0700 (PDT) (envelope-from PeterJeremy@optushome.com.au) Received: from cirb503493.alcatel.com.au (localhost.alcatel.com.au [127.0.0.1])h9LKQJf1011749; Wed, 22 Oct 2003 06:26:19 +1000 (EST) (envelope-from jeremyp@cirb503493.alcatel.com.au) Received: (from jeremyp@localhost)h9LKQIdP011748; Wed, 22 Oct 2003 06:26:18 +1000 (EST) (envelope-from jeremyp) Date: Wed, 22 Oct 2003 06:26:18 +1000 From: Peter Jeremy To: Robert Watson Message-ID: <20031021202618.GE1668@cirb503493.alcatel.com.au> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.1i cc: current@freebsd.org Subject: Re: ethercons: ethernet console driver for 5-current X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 21 Oct 2003 20:26:27 -0000 On Mon, Oct 20, 2003 at 12:13:27PM -0400, Robert Watson wrote: > After reading a FREENIX >paper this summer on a Linux ethernet console driver, I took a pass at >implementing ethernet console support for FreeBSD. A very worthy cause. I'm sure this has come up before but I think you're the first person to produce actual code. Something that you don't seem to address is security - which surprised me. > This driver is similar >to the Linux driver, although not binary-compatible on the wire, >... >As with the Linux driver, communication happens at the ethernet link >layer, using protocol number 0x0666 (entertaining choice). If Linux is using 0x0666, we should probably pick a different number since we're not wire compatible. Though coming up with a common protocol would be even better. > In general, the wire protocol is >probably the weakest part of the endeavor, but I'm having trouble finding >documentation for a decent wire console protocol that doesn't come with an >entire network stack attached. MOP (as you point out later) or LAT have the advantage of being more standard, but I'm not sure how well documented they are. > A series of tunables and sysctls is available to tune the >behavior of ethercons: >kern.ethercons.ifnet_raise >kern.ethercons.interface_preference >kern.ethercons.target Is there any way to specify ifconfig options? "media" and "mediaopts" in particular may need to be specified to get the interface to talk to the associated switch. I presume kern.ethercons.target only specifies the MAC address inserted into transmitted packets. Is there any way to restrict the src address(es) of received packets? Does ethercons have any concept of a current session or will it accept incoming packets from anywhere at any time? The latter case would seem undesirable as (IMHO) it makes it too easy to accidently send a command to the wrong system Peter